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1.
Proc Natl Acad Sci U S A ; 113(51): 14507-14514, 2016 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-27911770

RESUMO

Healthy ocean ecosystems are needed to sustain people and livelihoods and to achieve the United Nations Sustainable Development Goals. Using the ocean sustainably requires overcoming many formidable challenges: overfishing, climate change, ocean acidification, and pollution. Despite gloomy forecasts, there is reason for hope. New tools, practices, and partnerships are beginning to transform local fisheries, biodiversity conservation, and marine spatial planning. The challenge is to bring them to a global scale. We dissect recent successes using a complex adaptive-systems (CAS) framework, which acknowledges the interconnectedness of social and ecological systems. Understanding how policies and practices change the feedbacks in CASs by altering the behavior of different system components is critical for building robust, sustainable states with favorable emergent properties. Our review reveals that altering incentives-either economic or social norms, or both-can achieve positive outcomes. For example, introduction of well-designed rights-based or secure-access fisheries and ecosystem service accounting shifts economic incentives to align conservation and economic benefits. Modifying social norms can create conditions that incentivize a company, country, or individual to fish sustainably, curb illegal fishing, or create large marine reserves as steps to enhance reputation or self-image. In each example, the feedbacks between individual actors and emergent system properties were altered, triggering a transition from a vicious to a virtuous cycle. We suggest that evaluating conservation tools by their ability to align incentives of actors with broader goals of sustainability is an underused approach that can provide a pathway toward scaling sustainability successes. In short, getting incentives right matters.


Assuntos
Conservação dos Recursos Naturais , Motivação , Oceanos e Mares , Animais , Biodiversidade , Mudança Climática , Ecologia , Ecossistema , Pesqueiros , Peixes , Humanos , Política Pública
2.
J Virol ; 83(2): 734-47, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18987135

RESUMO

Epstein-Barr Virus (EBV) glycoprotein B (gB) is essential for viral fusion events with epithelial and B cells. This glycoprotein has been studied extensively in other herpesvirus family members, but functional domains outside of the cytoplasmic tail have not been characterized in EBV gB. In this study, a total of 28 linker insertion mutations were generated throughout the length of gB. In general, the linker insertions did not disrupt intracellular expression and variably altered cell surface expression. Oligomerization was disrupted by insertions located between residues 561 and 620, indicating the location of a potential site of oligomer contacts between EBV gB monomers. In addition, a novel N-glycosylated form of wild-type gB was identified under nonreducing Western blot conditions that likely represents a mature form of the protein. Fusion activity was abolished in all but three variants containing mutations in the N-terminal region (gB30), within the ectodomain (gB421), and in the intracellular C-terminal domain (gB832) of the protein. Fusion activity with variants gB421 and gB832 was comparable to that of the wild type with epithelial and B cells, and only these two mutants, but not gB30, were able to complement gB-null virus and subsequently function in virus entry. The mutant gB30 exhibited a low level of fusion activity with B cells and was unable to complement gB-null virus. The mutations generated here indicate important structural domains, as well as regions important for function in fusion, within EBV gB.


Assuntos
Herpesvirus Humano 4/fisiologia , Mutagênese Insercional , Proteínas Virais/fisiologia , Internalização do Vírus , Animais , Linfócitos B/virologia , Linhagem Celular , Cricetinae , Cricetulus , Células Epiteliais/virologia , Teste de Complementação Genética , Glicosilação , Herpesvirus Humano 4/genética , Humanos , Domínios e Motivos de Interação entre Proteínas , Multimerização Proteica , Estrutura Terciária de Proteína , Proteínas Virais/genética
3.
J Org Chem ; 75(10): 3518-21, 2010 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-20420397

RESUMO

Unsymmetrical diarylalkynes are accessible by a one-pot procedure from two different aryl halides and (trimethylsilyl)acetylene. The three-component coupling is initialized by a Pd/Cu-catalyzed Sonogashira coupling of an aryl halide with (trimethylsilyl)acetylene. After subsequent desilylation of the formed aryl(trimethylsilyl)acetylene with aqueous potassium hydroxide, a second Sonogashira coupling with an aryl iodide that does not require any additional Pd/Cu-catalyst gives access to an unsymmetrical diarylalkyne.


Assuntos
Alcinos/síntese química , Alcinos/química , Estrutura Molecular , Estereoisomerismo
5.
Sci Rep ; 7(1): 8940, 2017 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-28827603

RESUMO

Marine protected areas (MPAs) are a cornerstone of marine conservation. Globally, the number and coverage of MPAs are increasing, but MPA implementation lags in many human-dominated regions. In areas with intense competition for space and resources, evaluation of the effects of MPAs is crucial to inform decisions. In the human-dominated Mediterranean Sea, fully protected areas occupy only 0.04% of its surface. We evaluated the impacts of full and partial protection on biomass and density of fish assemblages, some commercially important fishes, and sea urchins in 24 Mediterranean MPAs. We explored the relationships between the level of protection and MPA size, age, and enforcement. Results revealed significant positive effects of protection for fisheries target species and negative effects for urchins as their predators benefited from protection. Full protection provided stronger effects than partial protection. Benefits of full protection for fish biomass were only correlated with the level of MPA enforcement; fish density was higher in older, better enforced, and -interestingly- smaller MPAs. Our finding that even small, well-enforced, fully protected areas can have significant ecological effects is encouraging for "crowded" marine environments. However, more data are needed to evaluate sufficient MPA sizes for protecting populations of species with varying mobility levels.


Assuntos
Conservação dos Recursos Naturais/métodos , Peixes/crescimento & desenvolvimento , Ouriços-do-Mar/crescimento & desenvolvimento , Animais , Biomassa , Ecossistema , Atividades Humanas , Humanos , Mar Mediterrâneo
6.
J Appl Anim Welf Sci ; 19(4): 385-95, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27135378

RESUMO

Environmental enrichment has been widely used to improve conditions for nonhuman animals in captivity. However, there is no consensus about the best way to evaluate the success of enrichments. This study evaluated whether the proportion of time spent interacting with enrichments indicated the proportion of overall behavioral changes. Six environmental enrichments were introduced in succession to 16 captive macaws, and interaction of the animals with them as well as the behaviors of the group were recorded before and during the enrichments. All of the enrichments affected the proportions of time spent in different behaviors. Macaws interacted more with certain items (hibiscus and food tree) than with others (a toy or swings and stairs), but introduction of the enrichments that invoked the least interaction caused as many behavioral changes as those that invoked the most. Moreover, feeding behavior was only affected by the enrichment that invoked the least interaction, a change not detected by a general analysis of enrichment effects. In conclusion, little interaction with enrichment does not mean little change in behavior, and the effects of enrichments are more complex than previously considered.


Assuntos
Comportamento Animal , Papagaios , Bem-Estar do Animal , Animais , Animais de Zoológico/psicologia , Meio Ambiente , Comportamento Alimentar , Feminino , Masculino
7.
PLoS One ; 10(8): e0135135, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26308521

RESUMO

While there is a persistent inverse relationship between latitude and species diversity across many taxa and ecosystems, deviations from this norm offer an opportunity to understand the conditions that contribute to large-scale diversity patterns. Marine systems, in particular, provide such an opportunity, as marine diversity does not always follow a strict latitudinal gradient, perhaps because several hypothesized drivers of the latitudinal diversity gradient are uncorrelated in marine systems. We used a large scale public monitoring dataset collected over an eight year period to examine benthic marine faunal biodiversity patterns for the continental shelf (55-183 m depth) and slope habitats (184-1280 m depth) off the US West Coast (47°20'N-32°40'N). We specifically asked whether marine biodiversity followed a strict latitudinal gradient, and if these latitudinal patterns varied across depth, in different benthic substrates, and over ecological time scales. Further, we subdivided our study area into three smaller regions to test whether coast-wide patterns of biodiversity held at regional scales, where local oceanographic processes tend to influence community structure and function. Overall, we found complex patterns of biodiversity on both the coast-wide and regional scales that differed by taxonomic group. Importantly, marine biodiversity was not always highest at low latitudes. We found that latitude, depth, substrate, and year were all important descriptors of fish and invertebrate diversity. Invertebrate richness and taxonomic diversity were highest at high latitudes and in deeper waters. Fish richness also increased with latitude, but exhibited a hump-shaped relationship with depth, increasing with depth up to the continental shelf break, ~200 m depth, and then decreasing in deeper waters. We found relationships between fish taxonomic and functional diversity and latitude, depth, substrate, and time at the regional scale, but not at the coast-wide scale, suggesting that coast-wide patterns can obscure important correlates at smaller scales. Our study provides insight into complex diversity patterns of the deep water soft substrate benthic ecosystems off the US West Coast.


Assuntos
Organismos Aquáticos/classificação , Biodiversidade , Conservação dos Recursos Naturais , Geografia
8.
PLoS One ; 10(7): e0133301, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26200354

RESUMO

With the ongoing crisis of biodiversity loss and limited resources for conservation, the concept of biodiversity hotspots has been useful in determining conservation priority areas. However, there has been limited research into how temporal variability in biodiversity may influence conservation area prioritization. To address this information gap, we present an approach to evaluate the temporal consistency of biodiversity hotspots in large marine ecosystems. Using a large scale, public monitoring dataset collected over an eight year period off the US Pacific Coast, we developed a methodological approach for avoiding biases associated with hotspot delineation. We aggregated benthic fish species data from research trawls and calculated mean hotspot thresholds for fish species richness and Shannon's diversity indices over the eight year dataset. We used a spatial frequency distribution method to assign hotspot designations to the grid cells annually. We found no areas containing consistently high biodiversity through the entire study period based on the mean thresholds, and no grid cell was designated as a hotspot for greater than 50% of the time-series. To test if our approach was sensitive to sampling effort and the geographic extent of the survey, we followed a similar routine for the northern region of the survey area. Our finding of low consistency in benthic fish biodiversity hotspots over time was upheld, regardless of biodiversity metric used, whether thresholds were calculated per year or across all years, or the spatial extent for which we calculated thresholds and identified hotspots. Our results suggest that static measures of benthic fish biodiversity off the US West Coast are insufficient for identification of hotspots and that long-term data are required to appropriately identify patterns of high temporal variability in biodiversity for these highly mobile taxa. Given that ecological communities are responding to a changing climate and other environmental perturbations, our work highlights the need for scientists and conservation managers to consider both spatial and temporal dynamics when designating biodiversity hotspots.


Assuntos
Organismos Aquáticos/fisiologia , Biodiversidade , Peixes/fisiologia , Animais , Oceano Pacífico , Estados Unidos
9.
Virology ; 413(1): 26-38, 2011 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-21376360

RESUMO

Glycoproteins gB and gH/gL are required for entry of Epstein-Barr virus (EBV) into cells, but the role of each glycoprotein and how they function together to mediate fusion is unclear. Analysis of the functional homology of gB from the closely related primate gammaherpesvirus, rhesus lymphocryptovirus (Rh-LCV), showed that EBV gB could not complement Rh gB due to a species-specific dependence between gB and gL. To map domains of gB required for this interaction, we constructed a panel of EBV/Rh gB chimeric proteins. Analysis showed that insertion of Rh gB from residues 456 to 807 restored fusion function of EBV gB with Rh gH/gL, suggesting this region of gB is important for interaction with gH/gL. Split YFP bimolecular complementation (BiFC) provided evidence of an interaction between EBV gB and gH/gL. Together, our results suggest the importance of a gB-gH/gL interaction in EBV-mediated fusion with B cells requiring the region of EBV gB from 456 to 807.


Assuntos
Herpesvirus Humano 4/fisiologia , Lymphocryptovirus/metabolismo , Glicoproteínas de Membrana/metabolismo , Chaperonas Moleculares/metabolismo , Proteínas do Envelope Viral/química , Proteínas do Envelope Viral/metabolismo , Proteínas Virais/metabolismo , Internalização do Vírus , Sequência de Aminoácidos , Infecções por Vírus Epstein-Barr/virologia , Herpesvirus Humano 4/química , Herpesvirus Humano 4/genética , Lymphocryptovirus/química , Lymphocryptovirus/fisiologia , Glicoproteínas de Membrana/química , Glicoproteínas de Membrana/genética , Chaperonas Moleculares/química , Chaperonas Moleculares/genética , Dados de Sequência Molecular , Ligação Proteica , Estrutura Terciária de Proteína , Alinhamento de Sequência , Proteínas do Envelope Viral/genética , Proteínas Virais/química , Proteínas Virais/genética
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